Edge-loading tape cassette holders have been in use for some years. Such units are disclosed, for example, in U.S. Pat. Nos. 3,612,432 and 3,766,327. Generally, this type of holder includes a frame which supports the magnetic read/write head. The frame is formed with guides or stops adjacent the read/write head which positions the active edge of the cassette so that the exposed section of tape engages the head. The frame also supports drive spindles to move the tape and includes some sort of retainer for supporting the cassette on the spindles.
The cassette is inserted active edge first into the holder and the retainer positions the cassette either in an operating plane or in a loading plane. In the former plane, the cassette is oriented so that the recording head engages the tape in the cassette and the drive spindles project into the usual sprocket holes in the side of the cassette. In the latter plane, the cassette is angled relative to the operating plane so that the cassette is free of the drive spindle and can be grasped by the operator and withdrawn from the tape deck. The retainer which supports the cassette is swingable between two positions to move the cassette between its aforesaid loading and operating planes.
Edge loading, reel-to-reel driving tape decks should have wide application, particularly in connection with computer data storage and transfer operations. This is because it is mechanically a simpler system than the tape decks most commonly used which hold a standard Phillips cassette and shown, for example, in U.S. Pat. Nos. 3,394,898 and 3,394,899. More particularly, the tape holder of the general type with which we are concerned here does not depend upon a capstan to advance the tape. Consequently, it does not require the relatively complex cassette shift mechanism or capstan retract arrangement required to position the standard Phillips cassette so that the tape engages the recording head and the capstan projects properly into the cassette.
However, some problems do exist with the edge loading types of tape holders. The cassette may become hung up on the drive spindles as it is loaded into the holder. Also the cassette may not be held securely enough, particularly in its loading position. Indeed, some cassettes have actually fallen out of the holder onto the floor, resulting in damage to the tape or cassette.
Other problems have been encountered with prior edge loading tape decks. For example, some are not rugged and reliable enough for sustained usage, particularly in computer applications. The repeated loading and unloading of the cassettes may affect the holder so that it no longer properly positions the cassette. Also certain parts of the holder may tend to lose their effectiveness because of wear. Additionally, prior cassette holders of this general type have tended to be relatively complex and therefore expensive and difficult to repair and maintain. Finally, in the case of some conventional holders of this general type, the user has to take considerable care when positioning the cassette in the holder when moving the retainer to its operating position. Otherwise, the holder's cassette retainer does not close and lock properly.